1. Field of the Invention
The present invention relates generally to an identification device for a necked container, and more particularly, to a fixed identification collar that is attachable to the neck of a container and that has information encoded thereon which can be read either manually or automatically.
2. Prior Art
A wide variety of industries employ reusable containers for transporting and dispensing consumable products. These containers generally are expensive and are subjected to a wide variety of environmental conditions during transportation and use. A container of particular interest is that used to store pressurized gas such as oxygen, nitrogen and the like. Such containers commonly are referred to as "cylinders" or "gas cylinders," and those terms will be used hereafter to describe one particular type of container for which the invention has applicability.
In many applications it is necessary to be able to identify each individual cylinder by its serial number or other identifying information such as cylinder type, weight or contents. For convenience, such identifying information will be referred to hereafter as "cylinder data." The identification of cylinder data is a particular problem in the industrial gas industry wherein it is desirable to have cylinder data affixed to each cylinder in an encoded form to facilitate automatic reading of the cylinder data for input to a computerized inventory control system.
One method previously proposed for identifying pressurized gas containers has been to paint or stencil the cylinder data on the body or neck portion of the cylinder. A problem with this method resides in the impermanent nature of the painted or stenciled numbers or other identification markings. Because large numbers of cylinders are frequently transported on open trucks, they are often subjected to abrasive environmental conditions which tend to wear or degrade the quality of the markings. Also during loading and unloading operations, the cylinders are sometimes handled relatively roughly which tends to degrade, chip or smear the cylinder identification markings. As the markings become less legible, the chances for incorrect identification or a total loss of identification increase. In addition, this method of identifying cylinders is not well suited for automatic reading of cylinder data.
Another method of affixing information to the cylinders consists of inscribing the information on the walls or neck of the cylinder itself. However, in order to maintain the integrity of the cylinders themselves, the identification information can only be superficially inscribed and therefore has a tendency to become illegible. Also, the harsh environmental conditions to which the cylinders are subjected can cause oxidation of the cylinders, again tending to render the inscribed information illegible. This method of identifying gas cylinders also does not lend itself to automated reading of cylinder data.
Another method used to affix cylinder data to gas cylinders is to chemically bond an identification plate or label to the walls or neck of the gas cylinder container. A problem with this method resides with the fact that the material of which the plate or label is manufactured or stamped is usually of a material different from that of which the gas cylinder is made. Due to different thermal expansion characteristics of the two materials, a change in temperature will cause each of the two materials to expand or contract at a different rate, thereby weakening the chemical bonding between the materials and eventually resulting in a loss of adhesion.
Yet an additional technique for affixing cylinder data to gas cylinders is disclosed in U.S. Pat. No. 3,787,993. In the '993 patent, a gas cylinder is provided with two circumferential grooves located adjacent each other near the upper end of the cylinder. A color-coded elastic band having cylinder data on each side is stretched over the cylinder and then fitted into one of the grooves. Upon the occurrence of an event having relevance to the cylinder or its contents, the band can be stretched and turned over into the adjacent groove, thereby presenting a different color and different information for observance. Unfortunately, the band is not permanent in the sense that it can be repositioned and possibly removed. Further, because the band is elastic, it is possible for the band to be broken inadvertently if it is stretched too far. Also, the band can lose its elasticity or color after long periods in harsh environmental and handling conditions.
In order to facilitate inventory control and accountability of numerous pressurized gas cylinders, there remains a need to be able to permanently affix cylinder data which can be either manually or automatically interpreted and which is capable of long term association with the container being identified and which will maintain its integrity over long periods in harsh environmental and handling conditions.